DRILL Russian patent published in 1999 - IPC

FIELD: drilling tools. SUBSTANCE: drill has solid body made of hard alloy, cutting edges located at operating end of body, zone of coupling with drive spindle of metal-cutting machine tool. This zone is positioned at other end of body. Drill also has channels passing through body close to each other primarily in longitudinal direction, outcoming to body operating end and intended for passing of liquid agent from side of coupling zone towards cutting edges. Drill contains plate overlapping mouths of the channels which does not pass liquid. It is spaced from adjacent cutting edge and is intended for forming of liquid passage coupling spatially the mouths of channels. The latter are positioned so as to form several loops of cooling agent in closed circulation circuit. One pair of channels is provided with mouths arranged on operating end in zone of cutting edge surface. Drill ensures heat removal from cutting edges without using of cutting fluid. EFFECT: higher efficiency. 10 cl, 6 dwg